Polythiol compounds have been used as synthetic raw materials for obtaining various resins (see Japanese Patent Application Laid-open No. H07-252207 (the entire disclosure of which is hereby specifically incorporated by reference)). For example, a polythiourethane resin can be synthesized by a curing reaction of a polythiol compound and a polyiso(thio)cyanate compound. The polythiourethane resin thus obtained is useful as a material for various optical components such as spectacle lenses.